The present invention relates to a turning tool for machining the edges of plastic spectacle lenses in a machine for machining the edges of lenses.
To machine the edges of plastic lenses to the desired circumference, cutting tools are used that preferably have a single cutting tooth, although they may also be provided with three cutting teeth. If the lens is made of soft yet tough material, such as a polycarbonate, the cutting tooth or cutting teeth leave transverse grooves on the edges of the lenses; these transverse grooves resemble marks made from stopping. These grooves are particularly prevalent after the cutter has been used for a long period of time. The occurrence of such transverse grooves is even more pronounced with the newer type of machines for machining the edges of lenses, because these machines provide for a cyclical turning of the template and the lens. A bevel is produced via a groove in the cutter that determines the circumference.
It is an object of the present invention to provide a turning tool that accelerates and simplifies machining of the periphery of a lens to the desired shape via structurally straightforward means.